Manufacturing Bits: Jan. 3

3D printed military drones
The U.S. Army Research Laboratory has begun testing 3D printed drones for use in on-demand military missions.

The technology, called the On-Demand Small Unmanned Aircraft System (ODSUAS), enables a soldier to input the mission requirements in software. Then, a 3D printer devises the optimal configuration for an unmanned aerial vehicle. And it’s printed and delivered within 24 hours.

With the technology, researchers printed a Picatinny rail in about two-and-a-half hours. A Picatinny rail is a bracket used to mount a small arms weapon, such as an M4 carbine. The M4 carbine is an assault rifle used by the U.S. military.

The 3-D printed On-Demand Small Unmanned Aircraft System, or ODSUAS, flies at speeds of up to 55 miles per hour. (U.S. Army photo by Angie DePuydt)

The Army continues to collaborate with partners at the Georgia Tech’s Aerospace Systems Design Lab as they continue to refine technologies for future soldiers. “Drones or quadcopters are really getting big right now, I mean in particular just the commercial and hobby markets have shown what can be done with a small amount of money,” said John Gerdes, an engineer with the U.S. Army Research Laboratory. “Additive manufacturing or 3-D printing has become huge and everybody knows all the great things that can be done with 3-D printers. So we figured let’s assemble these two new technologies and provide a solution to soldiers that need something right now and don’t want to wait for it.”

GaN jammers
The gallium nitride (GaN) device market is heating up for both power semiconductor and RF applications. In the RF space, GaN can amplify high-power RF signals at microwave frequencies. GaN also reduces the size, weight, power and cost of a system.

The military sector is one of the early adopters for GaN. For example, the U.S. Air Force Research Laboratory and the U.S. Department of Defenserecently awarded Raytheon a $14.9 million contract to further enhance its process for producing RF GaN technology.

The new agreement follows a previous contract, which was completed in 2013. The new contract aims to increase the performance, yield and reliability of Raytheon’s GaN-based devices. The devices are fabricated in Raytheon’s foundry.

The first devices will be incorporated into Raytheon Space and Airborne Systems’ Next Generation Jammer (NGJ) program, which is scheduled for initial production in 2018. Raytheon’s NGJ solution will provide airborne electronic attack and jamming capabilities.

GaN is also used in a broad spectrum of military radar and defense systems. “We have only scratched the surface when it comes to harnessing the game-changing power that gallium nitride technology can bring to military applications,” said Colin Whelan, vice president of Advanced Technology in Raytheon’s Integrated Defense Systems business unit. “This contract will build on the 17-year, two-hundred-plus million-dollar investment Raytheon has made in maturing GaN. Over the next two years, we will further refine our GaN process to push the limits of radio frequency performance while maintaining or increasing yield and reliability.”

5G networksHRL Laboratories, an R&D lab venture between Boeing and General Motors, recently presented a paper on the development of a GaN HEMT technology with a ft >400-GHz and an fmax >550-GHz.

HRL’s GaN technology has a breakdown voltage that is five times greater than other technologies, such as silicon, SiGe, InP and GaAs. With the technology, HRL has devised the first generation of MMIC power amplifiers (PAs). The power added efficiency (PAE) for the technology is 59% at a frequency of 32-GHz, a bias of 3 volts and output power of 24.3-dBm.

The MMIC PAs could be used for next-generation 5G networks operating at 28- and 39-GHz. The technology would extend the battery lifetime in mobile handsets, due to the PAE compared to competing semiconductor technologies.